leverage common functions from libnodejs (#339)

* leverage common functions from libnodejs - use package json parser - use project path parser to reduce code duplication Signed-off-by: Michael Dawson <[email protected]> * fix: replace use of os.Setenv with t.Setenv - reduce code and chance of missing cleanup afterwards Signed-off-by: Michael Dawson <[email protected]> --------- Signed-off-by: Michael Dawson <[email protected]>
paketo-buildpacks · Aug 4, 2023 · 3642c2f · 3642c2f
1 parent 0bd3ec1
commit 3642c2f
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Showing 13 changed files with 82 additions and 397 deletions.
diff --git a/build.go b/build.go
@@ -4,22 +4,21 @@ import (
 	"fmt"
 	"path/filepath"
 
+	"github.com/paketo-buildpacks/libnodejs"
 	"github.com/paketo-buildpacks/packit/v2"
 	"github.com/paketo-buildpacks/packit/v2/scribe"
 )
 
-func Build(pathParser PathParser, logger scribe.Emitter) packit.BuildFunc {
+func Build(logger scribe.Emitter) packit.BuildFunc {
 	return func(context packit.BuildContext) (packit.BuildResult, error) {
 		logger.Title("%s %s", context.BuildpackInfo.Name, context.BuildpackInfo.Version)
 
-		projectPath, err := pathParser.Get(context.WorkingDir)
+		projectPath, err := libnodejs.FindProjectPath(context.WorkingDir)
 		if err != nil {
 			return packit.BuildResult{}, err
 		}
 
-		var pkg *PackageJson
-
-		pkg, err = NewPackageJsonFromPath(filepath.Join(projectPath, "package.json"))
+		pkg, err := libnodejs.ParsePackageJSON(projectPath)
 		if err != nil {
 			return packit.BuildResult{}, err
 		}

diff --git a/build_test.go b/build_test.go
@@ -2,7 +2,6 @@ package yarnstart_test
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -11,7 +10,6 @@ import (
 	"github.com/paketo-buildpacks/packit/v2"
 	"github.com/paketo-buildpacks/packit/v2/scribe"
 	yarnstart "github.com/paketo-buildpacks/yarn-start"
-	"github.com/paketo-buildpacks/yarn-start/fakes"
 	"github.com/sclevine/spec"
 
 	. "github.com/onsi/gomega"
@@ -25,7 +23,6 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		workingDir string
 		cnbDir     string
 		buffer     *bytes.Buffer
-		pathParser *fakes.PathParser
 
 		build packit.BuildFunc
 	)
@@ -54,10 +51,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		buffer = bytes.NewBuffer(nil)
 		logger := scribe.NewEmitter(buffer)
 
-		pathParser = &fakes.PathParser{}
-
-		pathParser.GetCall.Returns.ProjectPath = filepath.Join(workingDir, "some-project-dir")
-		build = yarnstart.Build(pathParser, logger)
+		build = yarnstart.Build(logger)
 	})
 
 	it.After(func() {
@@ -67,47 +61,49 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 	})
 
 	it("returns a result that builds correctly", func() {
-		result, err := build(packit.BuildContext{
-			WorkingDir: workingDir,
-			CNBPath:    cnbDir,
-			Stack:      "some-stack",
-			BuildpackInfo: packit.BuildpackInfo{
-				Name:    "Some Buildpack",
-				Version: "some-version",
-			},
-			Plan: packit.BuildpackPlan{
-				Entries: []packit.BuildpackPlanEntry{},
-			},
-			Layers: packit.Layers{Path: layersDir},
+		it.Before(func() {
+			t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 		})
-		Expect(err).NotTo(HaveOccurred())
 
-		Expect(result).To(Equal(packit.BuildResult{
-			Launch: packit.LaunchMetadata{
-				Processes: []packit.Process{
-					{
-						Type:    "web",
-						Command: "bash",
-						Args: []string{
-							"-c",
-							fmt.Sprintf("cd %s/some-project-dir && some-prestart-command && some-start-command && some-poststart-command", workingDir),
+		it("default", func() {
+			result, err := build(packit.BuildContext{
+				WorkingDir: workingDir,
+				CNBPath:    cnbDir,
+				Stack:      "some-stack",
+				BuildpackInfo: packit.BuildpackInfo{
+					Name:    "Some Buildpack",
+					Version: "some-version",
+				},
+				Plan: packit.BuildpackPlan{
+					Entries: []packit.BuildpackPlanEntry{},
+				},
+				Layers: packit.Layers{Path: layersDir},
+			})
+			Expect(err).NotTo(HaveOccurred())
+
+			Expect(result).To(Equal(packit.BuildResult{
+				Launch: packit.LaunchMetadata{
+					Processes: []packit.Process{
+						{
+							Type:    "web",
+							Command: "bash",
+							Args: []string{
+								"-c",
+								fmt.Sprintf("cd %s/some-project-dir && some-prestart-command && some-start-command && some-poststart-command", workingDir),
+							},
+							Default: true,
+							Direct:  true,
 						},
-						Default: true,
-						Direct:  true,
 					},
 				},
-			},
-		}))
-		Expect(pathParser.GetCall.Receives.Path).To(Equal(workingDir))
+			}))
+		})
 	})
 
 	context("when BP_LIVE_RELOAD_ENABLED=true in the build environment", func() {
 		it.Before(func() {
-			os.Setenv("BP_LIVE_RELOAD_ENABLED", "true")
-		})
-
-		it.After(func() {
-			os.Unsetenv("BP_LIVE_RELOAD_ENABLED")
+			t.Setenv("BP_LIVE_RELOAD_ENABLED", "true")
+			t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 		})
 
 		it("adds a reloadable start command that ignores package manager files and makes it the default", func() {
@@ -154,7 +150,6 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 					Direct: true,
 				},
 			}))
-			Expect(pathParser.GetCall.Receives.Path).To(Equal(workingDir))
 		})
 	})
 
@@ -167,6 +162,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 				}
 			}`), 0600)
 			Expect(err).NotTo(HaveOccurred())
+			t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 		})
 
 		it("returns a result with a valid start command", func() {
@@ -212,6 +208,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 				}
 			}`), 0600)
 			Expect(err).NotTo(HaveOccurred())
+			t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 		})
 
 		it("returns a result with a valid start command", func() {
@@ -258,6 +255,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 				}
 			}`), 0600)
 			Expect(err).NotTo(HaveOccurred())
+			t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 		})
 
 		it("returns a result with a valid start command", func() {
@@ -297,7 +295,6 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 
 	context("when the project-path env var is not set", func() {
 		it.Before(func() {
-			pathParser.GetCall.Returns.ProjectPath = workingDir
 			err := os.WriteFile(filepath.Join(workingDir, "package.json"), []byte(`{
 				"scripts": {
 					"prestart": "some-prestart-command",
@@ -351,6 +348,7 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 		context("when package.json does not exist", func() {
 			it.Before(func() {
 				Expect(os.RemoveAll(filepath.Join(workingDir, "some-project-dir", "package.json"))).To(Succeed())
+				t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 			})
 
 			it("fails with the appropriate error", func() {
@@ -367,13 +365,14 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 					},
 					Layers: packit.Layers{Path: layersDir},
 				})
-				Expect(err).To(MatchError(ContainSubstring(fmt.Sprintf("unable to open package.json: open %s", filepath.Join(workingDir, "some-project-dir", "package.json")))))
+				Expect(err).To(MatchError(ContainSubstring(fmt.Sprintf("open %s: no such file or directory", filepath.Join(workingDir, "some-project-dir", "package.json")))))
 			})
 		})
 
 		context("when package.json is malformed", func() {
 			it.Before(func() {
 				Expect(os.WriteFile(filepath.Join(workingDir, "some-project-dir", "package.json"), []byte("%%%"), os.ModePerm)).To(Succeed())
+				t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 			})
 
 			it("fails with the appropriate error", func() {
@@ -390,40 +389,14 @@ func testBuild(t *testing.T, context spec.G, it spec.S) {
 					},
 					Layers: packit.Layers{Path: layersDir},
 				})
-				Expect(err).To(MatchError(ContainSubstring("unable to decode package.json: invalid character")))
-			})
-		})
-
-		context("when the path parser returns an error", func() {
-			it.Before(func() {
-				pathParser.GetCall.Returns.Err = errors.New("path-parser-error")
-			})
-
-			it("returns an error", func() {
-				_, err := build(packit.BuildContext{
-					WorkingDir: workingDir,
-					CNBPath:    cnbDir,
-					Stack:      "some-stack",
-					BuildpackInfo: packit.BuildpackInfo{
-						Name:    "Some Buildpack",
-						Version: "some-version",
-					},
-					Plan: packit.BuildpackPlan{
-						Entries: []packit.BuildpackPlanEntry{},
-					},
-					Layers: packit.Layers{Path: layersDir},
-				})
-				Expect(err).To(MatchError("path-parser-error"))
+				Expect(err).To(MatchError(ContainSubstring("unable to decode package.json invalid character '%' looking for beginning of value")))
 			})
 		})
 
 		context("when BP_LIVE_RELOAD_ENABLED is set to an invalid value", func() {
 			it.Before(func() {
-				os.Setenv("BP_LIVE_RELOAD_ENABLED", "not-a-bool")
-			})
-
-			it.After(func() {
-				os.Unsetenv("BP_LIVE_RELOAD_ENABLED")
+				t.Setenv("BP_LIVE_RELOAD_ENABLED", "not-a-bool")
+				t.Setenv("BP_NODE_PROJECT_PATH", "some-project-dir")
 			})
 
 			it("returns an error", func() {

diff --git a/detect.go b/detect.go
@@ -6,21 +6,17 @@ import (
 	"path/filepath"
 	"strconv"
 
+	"github.com/paketo-buildpacks/libnodejs"
 	"github.com/paketo-buildpacks/packit/v2"
 	"github.com/paketo-buildpacks/packit/v2/fs"
 )
 
-//go:generate faux --interface PathParser --output fakes/path_parser.go
-type PathParser interface {
-	Get(path string) (projectPath string, err error)
-}
-
 // NoStartScriptError indicates that the targeted project does no have a start command in their package.json
 const NoStartScriptError = "no start script in package.json"
 
-func Detect(projectPathParser PathParser) packit.DetectFunc {
+func Detect() packit.DetectFunc {
 	return func(context packit.DetectContext) (packit.DetectResult, error) {
-		projectPath, err := projectPathParser.Get(context.WorkingDir)
+		projectPath, err := libnodejs.FindProjectPath(context.WorkingDir)
 		if err != nil {
 			return packit.DetectResult{}, err
 		}
@@ -34,12 +30,15 @@ func Detect(projectPathParser PathParser) packit.DetectFunc {
 			return packit.DetectResult{}, packit.Fail.WithMessage("no 'yarn.lock' found in the project path %s", projectPath)
 		}
 
-		var pkg *PackageJson
-		if pkg, err = NewPackageJsonFromPath(filepath.Join(projectPath, "package.json")); err != nil {
-			return packit.DetectResult{}, err
+		pkg, err := libnodejs.ParsePackageJSON(projectPath)
+		if err != nil {
+			if os.IsNotExist(err) {
+				return packit.DetectResult{}, packit.Fail.WithMessage("no 'package.json' found in project path %s", projectPath)
+			}
+			return packit.DetectResult{}, fmt.Errorf("failed to open package.json: %w", err)
 		}
 
-		if !pkg.hasStartCommand() {
+		if !pkg.HasStartScript() {
 			return packit.DetectResult{}, packit.Fail.WithMessage(NoStartScriptError)
 		}